The present invention relates to apparatuses and methods for separating liquid from gas.
Separators for separating liquid from gas are well known in the art. Separators are used, for example, to dry natural gas. The gas has liquid, such as water, entrained therein. If the natural gas is transported through pipelines in a xe2x80x9cwetxe2x80x9d condition, the water acts to Corrode the steel pipelines, causing possible ruptures and explosions. Thus, it is desirable to economically and effectively remove the water from natural gas, and in general, to remove various types of liquids from various types of gasses.
One prior art type of separator is taught by Hill et al., U.S. Pat. No. 3,813,855. The Hill patent teaches shaped vanes for channeling a fluid flow in a serpentine path. This path creates impact regions and sheltered regions, wherein the liquid in the fluid flow impacts the vanes and collects in the sheltered regions. Another prior art shaped separator is shown in Brown, U.S. Pat. No. 5,112,375.
The serpentine path separators typically require additional means to aid in the separation process. For example, in Regeher, U.S. Pat. No. 3,953,183, serrations are used on the vane surfaces for capturing and draining coalesced liquid. These type of separators are expensive to manufacture.
Another prior art technique uses serpentine path separators in conjunction with a fine wire mesh located at the inlet end of the vanes. The wire mesh increases the effectiveness of the separation; the fluid passes through the wire mesh before entering the vane channels and liquid coalesces on the wire mesh, dropping to the bottom of a tank containing the separator vanes.
The problem with using a wire mesh is that the mesh tends to become clogged with particulates and solids in the fluid stream. When the mesh becomes clogged or partially blocked, the overall efficiency in the separator becomes reduced.
It is an object of the present invention to provide a separator for separating liquid from gas in a fluid flow.
It is another object of the present invention to provide a separator with an increased efficiency and a smaller physical size.
The present invention provides a vane assembly for use in a separator for separating liquid from gas. The vane assembly comprises vanes spaced apart from and adjacent to one another and forming a serpentine path between any two adjacent vanes. The vanes have surfaces along the paths. The vanes have an inlet section and a downstream section. The inlet section of the vanes have vane surfaces with a first surface area per unit area. The downstream section has vane surfaces with a second surface area per unit area. The second surface area is smaller than the first surface area so that the vane surfaces of the inlet section are more wettable than the vane surfaces of the downstream section.
In accordance with one aspect of the present invention, the vane surfaces of the inlet section are roughened and the vane surfaces of the downstream section are smooth.
The present invention also provides an assembly for use in the separator for separating liquid from gas comprising corrugated plates with ridges and grooves. The plates are spaced apart from one another so as to form paths between the adjacent plates. The plates are oriented so that the ridges of any one plate are aligned with the ridges of an adjacent plate and the grooves of one any one plate are aligned with the grooves of an adjacent plate. The vane assembly has an upstream section and a downstream section. The upstream section of the plates has roughened plate surfaces while the downstream section of the plates has smooth plate surfaces.
In accordance with one aspect of the present invention, the roughened plate surfaces are blasted with a blasting media.
In accordance with another aspect of the present invention, the roughened plate surfaces have a roughness profile of 2-6 mils anchor pattern.
In accordance with another aspect of the present invention, the smooth plate surfaces are rolled smooth.
The present invention also provides a separator for separating liquid from gas comprising a vessel and a vane assembly located inside of the vessel. The vane assembly has vanes spaced apart from and adjacent to one another and forming a serpentine path between any two adjacent vanes. The vanes have surfaces along the paths. The vessel has inlet and outlet ports. The inlet port is aligned with an inlet section of the vane assembly. The inlet section of the vane assembly has roughened plate surfaces. The outlet port is aligned with an outlet section of the vane assembly, which outlet section has smooth plate surfaces.
In accordance with one aspect of the present invention, the roughened plate surfaces are blasted with a blasting media.
In accordance with another aspect of the present invention, the roughened plate surfaces have a roughness profile of 2-6 mils anchor pattern.
In accordance with still another aspect of the present invention, a separator for separating liquid from gas comprises a vessel and a vane assembly located inside of the vessel. The vane assembly has corrugated plates with ridges and grooves, with the plates being spaced apart from one another so as to form paths between adjacent plates. The plates are oriented so that the ridges of any one plate are aligned with the ridges of an adjacent plate and the grooves of any one plate are aligned with the grooves of an adjacent plate. The vessel has inlet and outlet ports. The inlet port is aligned with an inlet section of the vane assembly. The inlet section of the vane assembly has vane surfaces with a first surface area per unit area. The outlet port is aligned with an outlet section of the vane assembly, which outlet section has vane surfaces with a second surface area per unit area. The second surface area is smaller than the first surface area so that the vane surfaces of the inlet section are more wettable than the vane surfaces of the outlet section.
In accordance with one aspect of the present invention, the vane surfaces of the inlet section are roughened and the vane surfaces of the outlet section are smooth.
The present invention also provides a method of making a vane assembly. Corrugated plates are provided with each of the corrugated plates having ridges and grooves. A portion of the plates is blasted so as to create roughened surfaces while leaving another portion of the plates unblasted. The plates are aligned so as to be spaced apart from one another, with the ridges of any one plate aligned with the ridges of the other plates. The plates are oriented so that the roughened surfaces are located at an upstream end and the unblasted portions of the plates are located at a downstream end.
In accordance with one aspect of the present invention, the step of aligning the plates further comprises the step of generally aligning the plates in a parallel arrangement.
In accordance with another aspect of the present invention, the step of aligning the plates further comprises generally aligning the plates in a radial arrangement with the roughened surfaces near a center of the vane assembly than are the unblasted portions.
In accordance with still another aspect of the present invention, the step of blasting a portion of the plates further comprises blasting a first group of plates and leaving a second group of plates unblasted. The step of orienting the plates further comprises orienting the first group of plates in an end-to-end manner with the second group of plates.
The present invention also provides a method of separating liquid from a gas stream. The gas stream is flowed through a path and the gas stream is caused to change direction so as to impact the liquid on the sides of the path. The surface tension of the liquid on the sides of the path is reduced so as to cause coalescing of the liquid. Then, the surface tension of the liquid on the sides of the path is increased so as to allow the liquid to drain off of the sides.
In accordance with an aspect of the present invention, the surface tension of the liquid is reduced on the sides of the path by flowing the liquid over a roughened surface. The surface tension of the liquid on the side of the path is increased by flowing the liquid over a smooth surface.